Earphones can be used in a large range of applications including audio listening, communication technology, physiological sensing and environmental monitoring. Such earphones typically include an earpiece that is inserted into a user's ear.
Referring to FIG. 1, an ear 1 comprises an outer portion 2, middle portion 3 and inner portion 4. The outer portion comprises an auricle 5 that collects sound waves and guides them along an ear canal 6 to a tympanic membrane 7. A tragus (not shown) protrudes at least partially over the opening of the ear canal. At the middle ear, the sound waves strike the tympanic membrane causing it to vibrate. These vibrations are amplified by the bones of the ossicles 8. Once the amplified vibrations reach the inner ear they are converted into electrical impulses by a cochlea 9 and sent to the brain via an auditory nerve 10.
As can be seen in FIG. 2, the ear canal 6 is a generally S-shaped tube with a first bend 11 towards the rear of the skull and a second bend 12 towards the front of the skull. The ear canal inclines upwardly and the narrowest section lies between the first and second bends at an isthmus 13. In an adult, the length of the ear canal is approximately 20-30 mm, the width of the isthmus is approximately 4-7 mm, the height of the isthmus is approximately 6-10 mm and the angle of incline is approximately 24-26°.
Conventional earpieces sit in the auricle of the outer ear, blocking the opening of the ear canal. These earpieces can be ill-fitting and easy to dislodge. Users have found that these earpieces can be uncomfortable to wear and unsightly. The volume of sound produced by the earpieces may need to be adjusted to sufficiently counter ambient noise and prolonged use at this higher volume consumes higher power and may risk damaging a user's hearing. Due to their occlusion of the ear canal, users are also required to remove the earpieces when not in use.
The present invention seeks to overcome, or at least mitigate, the problems of the prior art. The present invention seeks to provide an improved earpiece for an earphone, an improved earphone comprising the earpiece and an improved earphone system.